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One-dimensional space

These six matrices can be verified to multiply just as the symmetry operations do thus they form another three-dimensional representation of the group. We see that in the Ti basis the matrices are block diagonal. This means that the space spanned by the Tj functions, which is the same space as the Sj span, forms a reducible representation that can be decomposed into a one dimensional space and a two dimensional space (via formation of the Ti functions). Note that the characters (traces) of the matrices are not changed by the change in bases. [Pg.588]

Figure 3.1 shows the evolution of a few legal rules, starting from an initial state consisting of a single nonzero value at the center site. In each case, and all such one-dimensional space-time patterns appearing in this book, the time axis runs from top to bottom and sites with value ctj — 1 are colored black. [Pg.54]

Information content in a powder diffraction pattern is reduced as compared to that in single crystal diffraction, due to the collapse of the three dimensional reciprocal space into a one dimensional space where the only independent variable is the scattering angle. The poorer the resolution of the diffraction method, the less the information content in the pattern (Altomare et al. 1995 David 1999). As a consequence, structure of less complex phases can be determined from power diffraction alone (fewer atoms in the asymmetric unit of the unit cell). However, refinement of the structure is not limited so seriously with resolution issues, so powder diffraction data are used in Rietveld refinement more frequently than in structure determination. Electron powder diffraction patterns can be processed and refined using public domain computer programs. The first successful applications of electron diffraction in this field were demonstrated on fairly simple structures. [Pg.194]

Fig. B-1 presents a steady-state flow in a combustion wave, showing mass, momentum, and energy transfers, including chemical species, in the one-dimensional space of Ax between Xj and %2- The viscous forces and kinetic energy of the flow are assumed to be neglected in the combustion wave. The rate of heat production in the space is represented by coQ, where ai is the reaction rate and Qis the heat release by chemical reaction per unit mass. Fig. B-1 presents a steady-state flow in a combustion wave, showing mass, momentum, and energy transfers, including chemical species, in the one-dimensional space of Ax between Xj and %2- The viscous forces and kinetic energy of the flow are assumed to be neglected in the combustion wave. The rate of heat production in the space is represented by coQ, where ai is the reaction rate and Qis the heat release by chemical reaction per unit mass.
The thermodynamic functions of fc-mers adsorbed in a simple model of quasi-one-dimensional nanotubes s adsorption potential are exactly evaluated. The adsorption sites are assumed to lie in a regular one-dimensional space, and calculations are carried out in the lattice-gas approximation. The coverage and temperature dependance of the free energy, chemical potential and entropy are given. The collective relaxation of density fluctuations is addressed the dependence of chemical diffusion coefficient on coverage and adsorbate size is calculated rigorously and related to features of the configurational entropy. [Pg.655]

At a surface of discontinuity in a three-dimensional space (or a line in a two-dimensional space, or a point in a one-dimensional space), the flux normal to the surface must be continuous, for the surface has no capacity to hold anything or volume to generate anything. Because there can be no accumulation in the surface, the flux up to it from one side must equal the flux away from it on the other. Thus,... [Pg.11]

More recently, Palais [17] showed that the generic cases of soliton—the Korteweg de Vries equation (KdV), the nonlinear Schrodinger equation (NLS), the sine-Gordon equation (SGE)—can be given an SU(2) formulation. In each of the three cases considered below, V is a one-dimensional space that is embedded in the space of off-diagonal complex matrices, ( ) and in each case L(u) at- I u, where u is a potential, i. is a complex parameter, and a is the constant, diagonal, trace zero matrix... [Pg.709]

Kant s problem concerning the right and the left hand, which cannot be made to coincide, exists even in two dimensions. Indeed, it exists in one-dimensional space,... [Pg.10]

Also, in this category of a mathematical ideal carbon compound that tessellates the one dimensional space is the infinite acetylene, which might be named as either ... [Pg.283]

The one-dimensional space groups are the simplest of the space groups. They have periodicity only in one direction. They may refer to one-dimensional, two-dimensional, or three-dimensional objects, cf., G, G, and G, of Table 2-2, respectively. The infinite carbon chains of the carbide molecules... [Pg.375]

Figure 8-4. Polar (a) And nonpolar (b) Decorations of Byzantine mosaics from Ravenna, Italy, with one-dimensional space-group symmetry (photographs by the authors). Figure 8-4. Polar (a) And nonpolar (b) Decorations of Byzantine mosaics from Ravenna, Italy, with one-dimensional space-group symmetry (photographs by the authors).
An important application of one-dimensional space groups is for polymeric molecules in chemistry. Figure 8-13 illustrates the structure and symmetry elements of an extended polyethylene molecule. The translation, or identity period, is shown, which is the distance between two carbon atoms separated by a third one. However, any portion with this length may be selected as the identity period along the polymeric chain. The translational symmetry of polyethylene is characterized by this identity period. [Pg.385]

Biological macromolecules are often distinguished by their helical structures to which one-dimensional space-group symmetries are applicable. Figure 8-15a shows Linus Pauling s sketch of a polypeptide chain, which he drew while he was looking for the structure of alpha-keratin. When he decided to fold the paper, he arrived at the alpha-helix. The solution may have come in a sudden moment,... [Pg.387]

I. Hargittai, G. Lengyel, The Seven One-Dimensional Space-Group Symmetries Illustrated by Hungarian Folk Needlework. ./ Chem. Educ. 1984, 61, 1033-1034. [Pg.410]

The equations depend essentially on six coordinates in the Cartesian space, and it includes a sixfold integral. This integral is the one that prevents the theory from applications to polyatomic molecules. It is the interaction-site model and the RISM approximation proposed by Chandler and Andersen [16] that enabled one to solve the equations. The idea behind the model is to project the functions onto the one-dimensional space along the distance between the interaction sites, usually placed on the center of atoms, by taking the statistical average over the angular coordinates of the molecules with fixation of the separation between a pair of interaction site. [Pg.192]

The rule = cos x is an example of a one-dimensional map, so-called because the points x belong to the one-dimensional space of real numbers. The sequence Xq, X, Xj,, . . is called the orbit starting from Xg. [Pg.348]


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0-dimensional space

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